JPH09112761A - Corrugated pipe fittings - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a corrugated pipe joint that can easily connect corrugated pipes, has high sealing property, and further has high strength and can maintain good sealing property for a long period of time. [Structure] A spiral groove 13 that is tightly screwed into the outer peripheral surface of a corrugated tube 50 is sandwiched between two attachments 11 formed on the inner peripheral surface of an elastic tubular body and a connection-side end surface of the two attachments. Annular seal ring 21 made of elastic material
And two cover halves each having a semicircular side wall 33 formed in contact with the non-connecting side end face of the attachment at both ends of each of the two tubular halves having a tubular shape surrounding the outer peripheral surface of the attachment. It comprises a body 31 and a coupling 41 for fixing the combined state of the two cover halves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint for connecting corrugated pipes having spiral grooves formed in a pipe wall at their ends.

[0002]

2. Description of the Related Art As a protection tube for protecting electric wires or cables buried in the soil from external water and the like,
A corrugated pipe made of rubber or the like having a spiral groove formed on a pipe wall is often used. Usually, the corrugated pipe is formed to have a predetermined length, and thus the corrugated pipe is used to have a desired length by connecting ends of the corrugated pipe with a joint.

Conventionally, there are the following joints for the corrugated pipe. One of them is a tubular member made of an elastic material, and the corrugated pipes are connected to each other by inserting the end portions of the corrugated pipe into the joint from both ends of the joint while rotating the joint or the corrugated pipe. It is a thing. At this time, in order to prevent external water from entering the corrugated pipe from the corrugated pipe connecting portion, putty is put on the spiral groove on the outer peripheral surface of the corrugated pipe connecting side end portion to be inserted into the joint. After filling and further inserting the corrugated pipe into the joint, tape is wrapped around the joint surface and the surface near the ends of the corrugated pipe exposed from both ends of the joint.

Other joints are shown in FIGS. 6 and 7. This joint 60 comprises a half-divided tubular body made of plastic (a tubular body divided into two along a direction orthogonal to its diameter) 61, and a spiral groove that engages with the outer peripheral surface of the corrugated pipe 50. It is composed of the formed packing 71, and the packing 71 is arranged on the inner surface of the half-divided tubular body 61. Then, the connection side ends of the corrugated pipes 50, 50 to be connected are butted, and the half-split tubular bodies 61, 61 are aligned so that the spiral irregularities of the outer circumferential surface of the corrugated pipes fit the spiral irregularities of the packing 71. Then, the outer peripheral surfaces of the connection side end portions of the corrugated pipes 50, 50 are connected to the two half-split tubular bodies 61, 61.
Then, the corrugated pipes 50, 50 are connected by tightening the projections 62, 62 formed on the outer surface of the combined portion of the half-split tubular body 61 with the screws 63 and the nut 64.

However, the conventional joint has the following problems. First, in the former joint, it is necessary to fill the putty and wind the tape when connecting the corrugated pipe,
There is a problem that the work is troublesome. Furthermore, it is difficult to say that the connection strength of the corrugated pipe is sufficient, and the connection portion of the corrugated pipe is easily loosened due to twisting or vibration during construction or the weight of soil above the corrugated pipe, and the strength decreases. There are also easy problems.

On the other hand, in the latter joint 60, by tightening the two half-split tubular bodies with screws or nuts,
Since the packing 71 surface is crimped to the outer peripheral surface of the corrugated pipe 50 to seal the outer peripheral surface of the connection side end of the corrugated pipe 50, the unit surface of the packing 71 must be tightened with a large force. The pressing force per area may not be sufficient, and the seal between the outer peripheral surface of the connection-side end portion 53 of the corrugated pipe may be partially defective.

Further, in the latter joint 60, the packing 71 is attached to the corrugated pipe 5 by tightening a plurality of screws or the like.
Since the outer peripheral surface of the end portion of No. 0 is crimped to the outer peripheral surface of the end portion of the corrugated pipe 50, the surface of the packing 71 cannot be crimped to the outer peripheral surface of the end portion of the corrugated pipe 50 with a uniform force unless the plurality of screws are uniformly tightened. is there. Moreover, the end surface of the connection side end portion 53 of the corrugated pipe 50 has the spiral groove 5 formed on the pipe wall of the corrugated pipe 50.
Because of the non-uniform surface due to 2, the end faces of the corrugated pipe 53 do not come into close contact with each other even if they are butted against each other, and a gap is created. Therefore, when the packing 71 and the outer peripheral surface of the connection side end portion 53 of the corrugated pipe 50 are not sufficiently sealed due to the tightening condition of the screws or the like, the combination portion 65 of the half-divided tubular bodies 61, 61 and the packing 71. Water enters the corrugated pipe 50 through the gap between the connection-side end portions 53 of the corrugated pipe from the combination portion.

The connecting side end portions 53, 5 of the two corrugated pipes
It is also conceivable to abut three of them together, wrap a seal tape around the outer periphery thereof and connect the corrugated pipe 50, and then fix the joint 60 to the outer peripheral surface of the connection side end of the corrugated pipe, but in that case, There is a problem that a step due to the thickness of the tape is generated on the surface of the connection side end portion 53 of the corrugated pipe 50, and the sealing property of the packing 71 is deteriorated.

In addition to these, in the latter joint 60, when the installation location of the cable or the like is narrow, there is a problem that the tool collides with the surroundings when tightening the screw or the like, which makes the work difficult. In addition, the protrusion 62 formed on the outer surface of the half-divided tubular body 61 has a screw-out amount (width) from the outer peripheral surface of the half-divided tubular body 61 so as to withstand the pressure when tightening a screw or the like. It is made considerably larger than the diameter of the nut. Therefore, there is also a problem that the protrusion 62 for the screw or the like interferes and a plurality of cables or the like cannot be arranged close to each other.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and can easily connect corrugated pipes with high sealing property and high strength for a long period of time. Therefore, the present invention aims to provide a corrugated pipe joint that can maintain a good sealing property.

[0011]

According to the present invention, in a joint for connecting two corrugated pipes each having a spiral groove formed in a pipe wall at an end thereof, the corrugated pipes are closely screwed to each other. A spiral groove is formed on the inner peripheral surface of the elastic tubular body, and is sandwiched between two attachments screwed to the outer peripheral surfaces of the connection side end portions of the two corrugated tubes and the connection side end surface of the two attachments. An annular seal ring made of an elastic material, and at both ends of the peripheral wall of each of the two half-divided tubular bodies having a tubular shape that surrounds the outer peripheral surface of the attachment by a combination, of the two attachments sandwiching the annular seal ring between the connection side end surfaces. Two cover halves having a semi-circular side wall formed in contact with the non-connection side end face and pressing the non-connection side end face toward the connection side end face side, and for fixing the combined state of the two cover halves. It's a tie It becomes possible according to the fitting of the corrugated tube, characterized in.

[0012]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a perspective view when connecting a corrugated pipe using a joint according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a state in which an attachment is fitted to one cover half body in the same embodiment, 3 is a sectional view of the same, FIG. 4 is a perspective view showing a state in which the coupler is mounted in the same embodiment, and FIG. 5 is a sectional view showing a connected state of the corrugated pipe in the same embodiment.

A joint 10 of an embodiment of the present invention shown in FIGS. 1 to 5 is for connecting corrugated pipes 50 having spiral grooves 52 formed in a pipe wall 51 to each other.
1, 11, annular seal ring 21, and cover half 3
1, 31 and couplings 41, 41. The two attachments 11 are the connection side end portions 53 of the corrugated pipe 50.
The spiral groove 13 that is screwed onto the outer peripheral surface of the corrugated tube 50 is formed on the inner peripheral surface of the elastic tubular body 12 made of an elastic material such as rubber.

The inner diameter of the attachment 11 is such that, when the attachment 11 is screwed onto the outer peripheral surface of the connection side end portion 53 of the corrugated pipe 50, the outer peripheral surface of the corrugated pipe 50 depends on its own elasticity and the elasticity of the corrugated pipe 50. The outer diameter of the corrugated pipe 50 is made the same as or slightly smaller than the outer diameter of the corrugated pipe 50 so that the attachment 11 closely adheres to and seals between the corrugated pipe 50 and the attachment 11. The outer diameter and length of the attachment 11 are appropriately determined depending on the strength of the attachment 11 and the sealing property between the connection-side end portion 53 of the corrugated pipe 50 and the attachment 11. On the other hand, this attachment 11
The spiral grooves 13 on the inner peripheral surface have the same pitch and the like so that they can be screwed into the spiral grooves 52 of the corrugated pipe 50. The spiral groove 13 may have a groove width and a groove depth different from those of the spiral groove 52 of the corrugated tube 50 so that the spiral grooves 13 and 53 are in close contact with each other for sealing.

Further, in the attachment 11 of this embodiment, the connecting side end portion 14 is bent inward to form an annular end wall 15, and an annular groove for fitting an annular seal ring is attached to an end surface 15a at the tip thereof. 16 are formed. The depth of the annular groove 16 is determined by the annular seal ring 21.
It is said that the depth cannot be completely buried inside. Further, the annular end wall 15 enhances the sealing property between the connection side end portion 53 of the corrugated pipe 50 and the attachment 11 and eliminates a sealing failure due to nonuniformity of the end face of the connection side end portion 53 of the corrugated pipe 50. Used to do. That is, the connection side end portion 5 of the corrugated pipe 50.
When the attachment 11 is screwed onto the connector 3, the end face of the connecting side end portion 53 of the corrugated pipe 50 is abutted against the inner end face 15b of the annular end wall 15 and the inner end face 15b thereof is elastically deformed. By closely contacting the end face of the connection-side end portion 53 of the corrugated pipe 50, the sealing property between the connection-side end portion 53 of the corrugated pipe 50 and the attachment 11 is enhanced.

The annular seal ring 21 is for compressing between the connection side end faces 15a, 15a of the two attachments 11, 11 to seal the connection side end faces 15a, 15a, and is made of an elastic material such as rubber. Consists of. The cross-sectional shape of the annular seal ring 21 may be substantially H-shaped instead of circular.

The two cover halves 31 have the attachments 11, 11 connected to the connection end faces 15a, 15 thereof.
It is for fixing the annular seal ring 21 in a compressed state between a and is made of a hard plastic such as polypropylene. The cover half body 31 has a shape in which semicircular side walls 33, 33 projecting inward are formed at both ends of a half-divided tubular body 32 which is obtained by dividing the tubular body in a direction orthogonal to the diameter thereof. The attachment 11,1
It becomes a tubular shape that surrounds the outer peripheral surface of 1.

The side walls 33, 33 are the end surfaces 18a of the non-connecting side ends 18 of the two attachments 11, 11.
18a and presses the non-connection side end surfaces 18a, 18a toward the connection side end surfaces 15a, 15a, thereby holding the attachments 11, 11 and an annular seal between the connection side end surfaces 15a, 15a. The ring 21 is compressed to seal between the attachments 11, 11.

The distance between the side walls 33, 33 is such that the annular seal ring 21 is in a non-compressed state and the connection side end faces 15a, 15 are formed.
It is made shorter than the distance between the non-connection side end faces 18a, 18a of the two attachments 11, 11 sandwiched between a, so that the annular seal ring 21 can be compressed.
The inner diameters of the side walls 33, 33 are equal to those of the cover halves 31, 3.
The outer peripheral surface and the side wall 3 of the corrugated pipe 50 when the combination of
The outer peripheral surface of the corrugated pipe 50 is the same as or larger than the outer peripheral surface of the corrugated pipe 50 so that the inner peripheral edges of the corrugated pipes 3, 33 do not interfere with the combination of the cover halves 31, 31.

Further, in the cover half body 31 of this embodiment, coupling projections 35, 35 projecting outward are formed along the combination portion 34 thereof in a substantially L-shaped cross section. The coupling projection 35 is for fixing the combined state of the two cover halves 31, 31 by a coupling tool 41 described later, and forms a groove 36 along the combination portion between the outer surface of the cover halves 31. Have. The coupling projection 35 is not limited to the above-mentioned shape, and in addition to the one in which the groove 36 is formed between the outer surface of the cover half body 31 and the outer surface of the coupling projection 35 as in this embodiment, the coupling projection 35 is A groove may be directly formed along the combination portion 34 on the outer surface of the projecting portion.

The connecting member 41 includes the cover halves 31, 31.
It is for fixing the combined state of the
2, 42 are formed of elongated metal fittings having a substantially U-shaped cross section formed on one side. The sandwiching pieces 42, 42 are fitted in the grooves 36, 36 on the outer surfaces of the coupling projections 35, 35 that are combined by the combination of the two cover halves 31, 31, and sandwich the outer surface. And this coupling tool 4
1 is made to slide from one end of the combined projections 35, 35, so that the holding piece 42 of the fitting 41,
42 is fitted in the grooves 36, 36 on the outer surface of the coupling projections 35, 35 and is mounted on the outer surface.

In the joint 10 having the above structure, corrugated pipes are connected as follows. First, as shown in FIG. 1, the attachments 11, 11 are screwed to the connection side ends of the corrugated tubes 50, 50. At that time, the connection side ends of the corrugated pipes 50, 50 are screwed from the non-connection side ends 18, 18 of the attachments 11, 11, and a predetermined amount of waves is applied to the connection side ends 14, 14 of the attachments 11, 11. Advance the connection side ends of the attached pipes 50, 50. Incidentally, the attachment 11 and the corrugated pipe 5
0 degree of contact or side wall 3 of the cover half 31
The corrugated pipe 50 may be left in a state where a gap is left between the corrugated pipe 50 and the annular end wall 15 of the attachment 11 depending on the intervals of 3, 33, etc., but the corrugated pipe 50 is attached to the inner end surface 15b of the annular end wall 15. The end face of the connection side end is crimped,
This is the most preferable because the attachment 11 and the corrugated pipe 50 can be more reliably sealed. Further, in order to facilitate rotation (screw engagement) of the attachment 11 or the corrugated pipe 50, a liquid adhesive, putty, or the like is attached to the attachment 1.
It may be applied to the spiral groove 13 of No. 1 or the spiral groove 52 on the outer peripheral surface of the connection side end of the corrugated pipe 50. After that, the adhesive or putty is cured to be attached 11 and the corrugated pipe 5.
Since 0 is strongly bonded, the strength of the connecting portion of the corrugated pipe can be increased, which is preferable.

Next, the annular seal ring 21 is fitted into the annular groove 16 of the joint side end surface 15a of the attachment 11,
The joint-side end surface 15a of the two attachments 11, 11,
The attachment 1 is disposed between the side walls 33, 33 of the cover half 31 as shown in FIGS.
1 and 11 and the annular seal ring 21 are stored. At that time, the non-connection side end faces 18a, 18a of the attachments 11, 11 are pressed toward the connection side end faces 15a, 15a by the side walls 33, 33 of the cover half body 31, and the connection side end face 15
The annular seal ring 21 between a is compressed. as a result,
Connection side end surfaces 15a, 15a of the attachments 11, 11.
The seal between them is made.

Then, as shown in FIG. 4, the cover halves 31, 31 are combined, and the coupling tool 41 is slid from the ends of the coupling projections 35, 35 of the cover halves 31, 31 which are combined by the combination. Then, the coupling tool 41 is attached to the coupling projections 35, 35. Thereby, the connecting projections 35, 3
5 is clamped by the coupler 41, the combined state of the cover halves 31, 31 is fixed, and the work of connecting the corrugated pipes 50, 50 is completed.

Corrugated pipes 50, 5 connected in this way
As shown in FIG. 5, the connection portion 0 of the corrugated tube 50 is sealed so that the connection-side end portion 53 of the corrugated pipe 50 is in close contact with the attachment 11.
Also, the attachment-side end surface 15 of the attachment 11, 11.
Since the annular seal ring 21 is compressed and sealed between a and 15a, the connection side end surface of the corrugated pipe 50 has the spiral groove 5 of the pipe wall.
2. Even if it is non-uniform, it is well sealed.

Moreover, the force for sealing between the attachments 11, 11, that is, the side wall 3 of the cover half body 31.
Since the pressing force of 3 and the joining force applied when the cover halves 31 and 31 are combined are orthogonal to each other, the sealing performance between the attachments 11 and 11 depends on how the cover halves 31 and 31 are joined, That is, corrugated tube 5
A good sealability is obtained without affecting the sealability of the 0, 50 joint.

Furthermore, the connecting portions of the corrugated pipes 50, 50 are the attachments 11, 11 and the cover halves 31, 31.
Since it is held by, the strength is increased.

Further, in this embodiment, the fixing of the combined state of the cover halves 31 and 31 is carried out by the coupling tool 41 which slides along the combined portion of the cover halves 31 and 31, so that the fixing is performed. Work can be done easily and in a small space. In addition, the coupling tool 41
Is not limited to the slide type, and may be a known coupling means such as a binding band. Even in that case, good sealing property and strength of the connection portion can be obtained.

When connecting corrugated pipes having different outer diameters, the two attachments 11 and 11 having different inner diameters are used according to the outer diameters of the corrugated pipes. The corrugated pipe can be surely connected.

[0030]

As shown and described above, according to the joint of the present invention, attachments made of elastic material are respectively screwed onto the outer peripheral surfaces of the connection side end portions of two corrugated pipes to be connected, and Since a corrugated pipe can be connected by sandwiching an annular seal ring between the connection-side end faces of two attachments and combining and joining the two cover halves on the outer peripheral face of the attachments, it is a troublesome work to wind the tape as in the past. Is unnecessary. Moreover, since the connection part of the corrugated pipe is held by the attachment and the two cover halves, the strength against twisting and vibration during construction or the weight of soil becomes high, and the corrugated pipe connection is good for a long time. Can be performed satisfactorily.

Further, according to the joint of the present invention, by pressing the non-connection side end surface of the attachment toward the connection side end surface side by the side walls of the two cover halves that are assembled on the outer peripheral surface of the attachment, the connection side end surface is pressed. The annular seal ring between the side end faces is compressed to seal the connecting portion of the corrugated pipe.
Therefore, the sealability is determined by the side wall spacing of the cover halves and is not affected by the degree of tightening of the two cover halves, and a constant sealability is always obtained.

Further, if the two cover halves are fixed by a slide type coupling tool, the corrugated pipe connection work can be performed easily and easily even in a narrow space. Even when the cables and the like are arranged close to each other, the corrugated pipe covered with the cables and the like can be easily connected.

In addition, even for the connection of two corrugated pipes having different outer diameters, the two attachments have their inner diameters matched with the outer diameters of the corrugated pipes, thereby making it simple and reliable. The corrugated pipe can be connected and the sealing property of the connecting portion can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view when connecting corrugated pipes using a joint according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a state in which an attachment is fitted to one cover half body in the embodiment.

FIG. 3 is a sectional view of FIG. 2;

FIG. 4 is a perspective view showing a state in which the coupler is mounted in the example.

FIG. 5 is a cross-sectional view showing a connected state of the corrugated pipe in the example.

FIG. 6 is a perspective view showing a usage state of a conventional joint.

FIG. 7 is a partially cutaway front view of the joint.

[Explanation of symbols]

 11 Attachment 13 Attachment Spiral Groove 14 Attachment Attachment End 18 Attachment Non-Connection End 21 Annular Seal Ring 31 Cover Half 33 Cover Half Sidewall 35 Cover Half Joining Protrusion 41 Coupling 50 Wave Attached tube

Claims (3)

[Claims] 1. A joint for connecting two corrugated pipes each having a spiral groove formed on a pipe wall at an end thereof, wherein the spiral groove that is tightly screwed to the outer peripheral surface of the corrugated pipe is inside the elastic tubular body. Two attachments that are formed on the peripheral surface and are screwed to each of the connection-side end outer peripheral surfaces of the two corrugated pipes, and an annular seal ring made of an elastic material sandwiched between the connection-side end surfaces of the two attachments. , The two ends of each of the two pipe-shaped half-divided tubular bodies that surround the outer peripheral surface of the attachment by combination are brought into contact with the non-connection-side end surfaces of the two attachments that sandwich the annular seal ring between the connection-side end surfaces. Two cover halves having a semi-annular side wall that presses the connection side end face toward the connection side end face side, and a coupling tool for fixing the combined state of the two cover halves, Corrugated pipe Joint. 2. The cover half body according to claim 1, wherein each of the two cover halves protrudes outwardly from an outer peripheral surface of the cover half body along a combination portion, and the outer surface thereof or between the outer surface and the outer surface of the cover half body. A coupling protrusion having a groove along the combination portion is formed, and the coupling member of the two cover halves sandwiches the outer surfaces of the two coupling protrusions that are combined by the combination of the two cover halves. One set has a pair of holding pieces that fit in the groove, and is mounted on the outer surfaces of the two coupling projections by sliding from the ends of the two coupling projections that have been fitted together. Corrugated pipe joint. 3. The wave according to claim 1, wherein the two attachments have different inner diameters and are screwed to the outer peripheral surfaces of the connection side end portions of the two corrugated pipes having different outer diameters. Fitting for attached pipe.